// Copyright 2022 The Tint Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include "src/tint/lang/wgsl/reader/parser/helper_test.h"

namespace tint::wgsl::reader {
namespace {

TEST_F(WGSLParserTest, IncrementDecrementStmt_Increment) {
    auto p = parser("a++");
    auto e = p->variable_updating_statement();
    EXPECT_TRUE(e.matched);
    EXPECT_FALSE(e.errored);
    EXPECT_FALSE(p->has_error()) << p->error();
    ASSERT_NE(e.value, nullptr);

    auto* i = e->As<ast::IncrementDecrementStatement>();
    ASSERT_NE(i, nullptr);
    ASSERT_NE(i->lhs, nullptr);

    ASSERT_TRUE(i->lhs->Is<ast::IdentifierExpression>());
    auto* ident_expr = i->lhs->As<ast::IdentifierExpression>();
    EXPECT_EQ(ident_expr->identifier->symbol, p->builder().Symbols().Get("a"));

    EXPECT_TRUE(i->increment);
}

TEST_F(WGSLParserTest, IncrementDecrementStmt_Decrement) {
    auto p = parser("a--");
    auto e = p->variable_updating_statement();
    EXPECT_TRUE(e.matched);
    EXPECT_FALSE(e.errored);
    EXPECT_FALSE(p->has_error()) << p->error();
    ASSERT_NE(e.value, nullptr);

    auto* i = e->As<ast::IncrementDecrementStatement>();
    ASSERT_NE(i, nullptr);
    ASSERT_NE(i->lhs, nullptr);

    ASSERT_TRUE(i->lhs->Is<ast::IdentifierExpression>());
    auto* ident_expr = i->lhs->As<ast::IdentifierExpression>();
    EXPECT_EQ(ident_expr->identifier->symbol, p->builder().Symbols().Get("a"));

    EXPECT_FALSE(i->increment);
}

TEST_F(WGSLParserTest, IncrementDecrementStmt_Parenthesized) {
    auto p = parser("(a)++");
    auto e = p->variable_updating_statement();
    EXPECT_TRUE(e.matched);
    EXPECT_FALSE(e.errored);
    EXPECT_FALSE(p->has_error()) << p->error();
    ASSERT_NE(e.value, nullptr);

    auto* i = e->As<ast::IncrementDecrementStatement>();
    ASSERT_NE(i, nullptr);
    ASSERT_NE(i->lhs, nullptr);

    ASSERT_TRUE(i->lhs->Is<ast::IdentifierExpression>());
    auto* ident_expr = i->lhs->As<ast::IdentifierExpression>();
    EXPECT_EQ(ident_expr->identifier->symbol, p->builder().Symbols().Get("a"));

    EXPECT_TRUE(i->increment);
}

TEST_F(WGSLParserTest, IncrementDecrementStmt_ToMember) {
    auto p = parser("a.b.c[2].d++");
    auto e = p->variable_updating_statement();
    EXPECT_TRUE(e.matched);
    EXPECT_FALSE(e.errored);
    EXPECT_FALSE(p->has_error()) << p->error();
    ASSERT_NE(e.value, nullptr);

    auto* i = e->As<ast::IncrementDecrementStatement>();
    ASSERT_NE(i, nullptr);
    ASSERT_NE(i->lhs, nullptr);
    EXPECT_TRUE(i->increment);

    ASSERT_TRUE(i->lhs->Is<ast::MemberAccessorExpression>());
    auto* mem = i->lhs->As<ast::MemberAccessorExpression>();

    EXPECT_EQ(mem->member->symbol, p->builder().Symbols().Get("d"));

    ASSERT_TRUE(mem->object->Is<ast::IndexAccessorExpression>());
    auto* idx = mem->object->As<ast::IndexAccessorExpression>();

    ASSERT_NE(idx->index, nullptr);
    ASSERT_TRUE(idx->index->Is<ast::IntLiteralExpression>());
    EXPECT_EQ(idx->index->As<ast::IntLiteralExpression>()->value, 2);

    ASSERT_TRUE(idx->object->Is<ast::MemberAccessorExpression>());
    mem = idx->object->As<ast::MemberAccessorExpression>();
    EXPECT_EQ(mem->member->symbol, p->builder().Symbols().Get("c"));

    ASSERT_TRUE(mem->object->Is<ast::MemberAccessorExpression>());
    mem = mem->object->As<ast::MemberAccessorExpression>();

    ASSERT_TRUE(mem->object->Is<ast::IdentifierExpression>());
    auto* ident_expr = mem->object->As<ast::IdentifierExpression>();
    EXPECT_EQ(ident_expr->identifier->symbol, p->builder().Symbols().Get("a"));
    EXPECT_EQ(mem->member->symbol, p->builder().Symbols().Get("b"));
}

TEST_F(WGSLParserTest, IncrementDecrementStmt_InvalidLHS) {
    auto p = parser("{}++");
    auto e = p->variable_updating_statement();
    EXPECT_FALSE(e.matched);
    EXPECT_FALSE(e.errored);
    EXPECT_FALSE(p->has_error()) << p->error();
    EXPECT_EQ(e.value, nullptr);
}

}  // namespace
}  // namespace tint::wgsl::reader
